Determination and dissolution of promethazine hydrochloride and caffeine tablets by HPLC / 国际药学研究杂志

ABSTRACT

Objective To develop a high performance liquid chromatography (HPLC) method for determining the content and dissolution of promethazine hydrochloride and caffeine tablets. Methods Agilent TC C18 column (250 mm×4.6 mm, 5 μm) was used. The mobile phase was methanol-3‰ triethylamine solution (adjusted to pH2.3 with phosphoric acid) (50 50, v/v) with a flow rate 1.0 ml/min, and the detection wavelengths were set at 250 nm and 272 nm, respectively. The column temperature was 30°C and the injection volume was 20 μl (injection volume of 10 μl for dissolution). Dissolution of tablets was determined by paddle method and the temperature was 37°C, 900 ml pH 1.2 hydrochloric acid solution, acetic acid buffer (pH 4.5), phosphoric acid buffer (pH 6.8) and water were used as dissolution medie at the rotation speed of 50, 75 r/min for selecting dissolution condition. Results The calibration curves were linear within the range of 0.5-100 μg/ml (r=1) for promethazine hydrochloride, and forcaffeine 4-400 μg/ml (r=0.9999), respectively. The detection limit and quantification limit of promethazine hydrochloride were 15 and 40 ng/ml, and caffeine 2 and 10 ng/ ml, respectively. The recoveries of promethazine hydrochloridum and caffeine were (100.04±1.39) % (n=9) and (99.42±1.07) % (n= 9), respectively. And the stability of working solutions was acceptable in 12 h. The method of dissolution tests for the tablet was established with 900 ml pH 1.2 hydrochloric acid solution as dissolution medium, paddle rotation speed of 50 r/min, and dissolution time 30 min. Conclusion The method is convenient, fast, sensitive and reproducible, with good precision, specificity and accuracy. So it can be used for simultaneous determination and dissolution of promethazine hydrochloride and caffeine tablet.